Swine wastewater can be used as a biofertilizer and promote significant improvements in soil physical-chemical attributes and yield. The objective of this study was to evaluate the effects of swine wastewater application on soil and maize yield. The experiment was conducted at the Agricultural Sciences Center of the Federal University of Piauí, in Teresina, Piauí, Brazil, from August to November 2015. The experimental design used completely randomized blocks in split-plot scheme, with five doses of swine wastewater (0, 25, 50, 75 and 100 m3 ha-1) in the plots and two soil depths (0.20 and 0.40 m) in the subplots, with four replications. Exchangeable contents of calcium, magnesium, phosphorus, potassium and sodium, electrical conductivity, pH, sum of bases, base saturation, potential acidity and cation exchange capacity, and crop yield were evaluated. Results showed calcium, magnesium, sum of bases and cation exchange capacity increased with elevated levels of swine wastewater. Potassium and sodium contents however decreased with doses of 51.58 and 52.28 m3 ha-1, respectively. Except for potassium and potential acidity, variables showed higher values at the 0-0.20 m depth.

Vegetable production is an impactful activity, characterized by intensive land use, high input demand, and it requires strategic management adoption, especially in sustainable production systems, where the pillars of sustainability (environmental, social and economic) must be respected. In this sense, the objective of this work was to evaluate economic indicators of lettuce production using Caatinga spontaneous species (Calotropis procera: rooster tree) as fertilizer and cultivated in two seasons (spring and fall-winter) in the municipality of Serra Talhada, PE. The experimental design was in randomized blocks, arranged in a 4 x 4 factorial scheme, with three replications. The first factor was the biomass amounts of green manure (5.4, 8.8, 12.2 and 15.6 t ha-1 on a dry basis); and the second was their incorporation times in the soil (0, 10, 20 and 30 days before lettuce transplanting). The green mass yield, production costs, rate of return, and net profit margin were determined. The amount 15.6 t ha-1 of C. procera allowed higher profitability to the organic production of lettuce, and it is considered ideal to incorporate the green manure 11 (spring) and 15 (fall-winter) days before transplanting the vegetable. The spring crop promoted a superior economic return to the fall-winter planting, demonstrating economic viability even in the smallest amount of C. procera.

Intercropping is a management strategy for the sustainability of agricultural systems, and is suitable for the production of vegetables. Kale is predominantly grown singly, but field observations have indicated that this crop has satisfactory productive potential when grown in intercrops with other vegetables. The objective of this work was to evaluate the agronomic performance and biological efficiency of kale plants intercropped with spice species. The experiment was carried out at the Didactic Horta of the Federal University of Ceará, Fortaleza, state of Ceará, Brazil. The experiment was conducted in a randomized block design with five replications. The treatments consisted of kale grown singly and intercropped with spice species (chives, coriander, basil, and parsley) and these spice species grown singly. The fresh and dry weights of the kale leaves, and the shoot of the spice species were evaluated. The biological efficiency was evaluated by the land use efficiency index (LUE), relative contribution of the kale crop to the LUE, area time equivalent ratio, and system productivity index. The intercropping of kale with parsley resulted in the highest fresh, and dry weights of kale leaves, showing the highest agronomic efficiency.

The number of studies on plant compounds with insecticidal activity has increased in recent years, and one of the primary targets of these compounds is leaf-cutter ants, which are considered the most important pests in Brazilian plantations, especially ants of the genus Atta. The objective of this study was to evaluate the toxic activity of the crude extract and fractions of the leaves of Esenbeckia pumila Pohl (Rutaceae) on Artemia salina and Atta sexdens rubropilosa and to perform a phytochemical study of this plant species. The toxicity of the extract and fractions was evaluated by determining the mean lethal concentration (LC50) on A. salina. The insecticidal activity was evaluated by feeding the ants an artificial diet containing the crude extract or fractions, and the results were analyzed using the log-rank test. The substances were isolated by chromatography, and the molecular structure was determined by spectroscopy. In the bioassay with A. salina, the ethanol extract and dichloromethane and ethyl acetate fractions were highly toxic. The analysis of survival curves indicated that the mortality rate of A. sexdens rubropilosa workers fed different fractions was higher than that of ants fed the control diet, especially the ethyl acetate fraction, with a mean survival time of 3 days and cumulative mortality of 100% on day 21 (p<0.05). The phytochemical study of this plant species allowed isolating the flavonoid rutin and a mixture of the triterpenes α-amyrin, β-amyrin, and lupeol. These results suggest the insecticidal potential of E. pumila on Atta sexdens rubropilosa.

ABSTRACT Intercropping is a management strategy for the sustainability of agricultural systems, and is suitable for the production of vegetables. Kale is predominantly grown singly, but field observations have indicated that this crop has satisfactory productive potential when grown in intercrops with other vegetables. The objective of this work was to evaluate the agronomic performance and biological efficiency of kale plants intercropped with spice species. The experiment was carried out at the Didactic Horta of the Federal University of Ceará, Fortaleza, state of Ceará, Brazil. The experiment was conducted in a randomized block design with five replications. The treatments consisted of kale grown singly and intercropped with spice species (chives, coriander, basil, and parsley) and these spice species grown singly. The fresh and dry weights of the kale leaves, and the shoot of the spice species were evaluated. The biological efficiency was evaluated by the land use efficiency index (LUE), relative contribution of the kale crop to the LUE, area time equivalent ratio, and system productivity index. The intercropping of kale with parsley resulted in the highest fresh, and dry weights of kale leaves, showing the highest agronomic efficiency. | RESUMO A consorciação de culturas é uma estratégia de manejo que visa a sustentabilidade dos agrossistemas, sendo adequada à produção de hortaliças. A couve é preponderantemente manejada sob cultivo solteiro, mas observações de campo tem indicado que a cultura tem potencial produtivo satisfatório quando cultivada em consórcio com outras hortaliças. Neste trabalho, avaliou-se o desempenho produtivo e a eficiência biológica do consórcio de couve com espécies condimentares. O experimento foi realizado na Horta didática da Universidade Federal do Ceará, Fortaleza - CE. Os tratamentos consistiram do cultivo de couve solteira e consorciada com espécies condimentares (cebolinha, coentro, manjericão e salsa), bem como seus respectivos cultivos solteiros. O delineamento experimental utilizado foi blocos ao acaso, com cinco repetições. Avaliou-se as massas fresca e seca das folhas de couve e da parte aérea para as espécies condimentares. A eficiência biológica foi avaliada pelo índice de uso eficiente da terra, contribuição relativa da cultura de couve ao UET, razão de área equivalente no tempo e índice de produtividade do sistema. O consórcio com salsa resultou nas maiores produções de massas fresca e seca de folhas de couve, mostrando-se com a maior eficiência agronômica.

RESUMO Objetivou-se avaliar a eficiência de produtos biológicos associados à adubação biológica no biocontrole de Pratylenchus brachyurus na cultura da soja, além do impacto destestratamentos sobre o desenvolvimento da cultura. O experimento foi conduzido em casa de vegetação, na UNEMAT, Campus de Tangará da Serra, com delineamento experimental em blocos casualizados, esquema fatorial 10X2, com quatro repetições. Foram avaliados: testemunha com e sem nematoides, Trichoderma asperellum, Bacillus subtilis, Purpureocillium lilacinum, B. subtilis+ T. asperellum, B. subtilis+ P. lilacinum, T. asperellum+ P. lilacinum, B. subtilis+ T. asperellum+ P. lilacinum e abamectina. Avaliou-se o nível populacional de P. brachyurus, altura, diâmetro do colo das plantas e características microbiológicas do solo aos 60 e 120 DAS; massa seca da parte aérea aos 60 DAS; número de vagens/planta e produtividade aos 120 DAS. Observou-se que aos 60 DAS os tratamentos promoveram eficiência no controle do fitonematoides, quando associados a adubação biológica somente os tratamentos biológicos melhoraram sua eficiência. Aos 120 DAS os produtos biológicos apresentaram maior eficiência no controle de P. brachyurus que a abamectina, aumentando sua eficiência quando adicionada a adubação biológica (nas duas épocas de semeadura). As características agronômicas, número de vagens/planta e produtividade submetidas aos tratamentos biológicos apresentaram melhor desempenho, havendo interação significativa entre tais tratamentos na primeira época de semeadura e interação com à aplicação do adubo biológico para estas variedades nas segunda época de semeadura. Com relação ás características microbiológicas do solo, houve interação entre os tratamentos somente com a aplicação da adubação biológica na segunda época de semeadura. | ABSTRACT The efficiency of biological products combined with biological fertilization for controlling Pratylenchus brachyurus in soybean crops, and effects of these treatments on soybean crops were evaluate. A greenhouse experiment was conducted at the Mato Grosso State University, in Brazil, using a randomized block design with a 10×2 factorial arrangement, and four replications. The treatments consisted of Trichoderma asperellum, B. subtilis, Purpureocillium lilacinum, B. subtilis + T. asperellum, B. subtilis + P. lilacinum, T. asperellum + P. lilacinum, B. subtilis + T. asperellum + P. lilacinum and abamectin, and Controls with, and without nematodes. Nematode population, plant height, stem base diameter, and soil microbiological characteristics (at 60 and 120 days after sowing - DAS), shoot dry weight (60 DAS), and number of pods per plant, and grain yield (120 DAS) were evaluated. The treatments were efficient for the control of phytonematodes at 60 DAS; the efficiency of treatments with biological products increased when combined with biological fertilization. The biological products were more efficient for controlling the nematodes than abamectin at 120 DAS; and the percentage of control were higher when they were combined with biological fertilization, in both growing periods. The biological treatments resulted in better agronomic characteristics, and higher number of pods per plant, and grain yield, affecting the plants in the first growing period, and significant interaction with the biological fertilizer for these variables in the second growing period. The interaction between treatments and biological fertilization was significant for soil microbiological characteristics in the second growing period.

ABSTRACT The number of studies on plant compounds with insecticidal activity has increased in recent years, and one of the primary targets of these compounds is leaf-cutter ants, which are considered the most important pests in Brazilian plantations, especially ants of the genus Atta. The objective of this study was to evaluate the toxic activity of the crude extract and fractions of the leaves of Esenbeckia pumila Pohl (Rutaceae) on Artemia salina and Atta sexdens rubropilosa and to perform a phytochemical study of this plant species. The toxicity of the extract and fractions was evaluated by determining the mean lethal concentration (LC50) on A. salina. The insecticidal activity was evaluated by feeding the ants an artificial diet containing the crude extract or fractions, and the results were analyzed using the log-rank test. The substances were isolated by chromatography, and the molecular structure was determined by spectroscopy. In the bioassay with A. salina, the ethanol extract and dichloromethane and ethyl acetate fractions were highly toxic. The analysis of survival curves indicated that the mortality rate of A. sexdens rubropilosa workers fed different fractions was higher than that of ants fed the control diet, especially the ethyl acetate fraction, with a mean survival time of 3 days and cumulative mortality of 100% on day 21 (p<0.05). The phytochemical study of this plant species allowed isolating the flavonoid rutin and a mixture of the triterpenes α-amyrin, β-amyrin, and lupeol. These results suggest the insecticidal potential of E. pumila on Atta sexdens rubropilosa. | RESUMO A avaliação de moléculas com atividade inseticida provenientes de plantas que apresentam atividade tóxica ou repelente cresceu nos últimos anos, tendo como um dos principais alvos de estudo as formigas cortadeiras, consideradas as principais pragas das plantações brasileiras, especialmente do gênero Atta. Sendo assim, o objetivo deste trabalho foi avaliar o potencial tóxico e inseticida do extrato bruto e frações das folhas de Esenbeckia pumila Pohl (Rutaceae) sobre Artemia salina e Atta sexdens rubropilosa e realizar o estudo fitoquímico daquela espécie. A avaliação da toxicidade do extrato e das frações foi realizada em bioensaio com A. salina determinando-se CL50 (Concentração Letal Média). A atividade inseticida foi avaliada pela ingestão do extrato e das frações incorporados a dieta artificial e os resultados foram tratados estatisticamente através do teste log rank. O isolamento de substâncias foi realizado por métodos cromatográficos e as estruturas determinadas pela análise de dados espectroscópicos. No bioensaio contra A. salina, o extrato etanólico e as frações diclorometânica e acetato-etílica se mostraram altamente tóxicas. A análise estatística das curvas de sobrevivência revelou taxas de mortalidade significativas de operárias de A. sexdens rubropilosa quando comparadas à dieta controle, com destaque para a fração acetato-etílica que apresentou sobrevivência mediana (Md) no 3o dia e mortalidade de 100% no 21o dia (p < 0,05). O estudo fitoquímico da espécie levou ao isolamento do flavanoide rutina e de uma mistura dos triterpenos α-amirina, β-amirina e lupeol. Esses resultados sugerem o potencial inseticida de E. pumila sobre Atta sexdens rubropilosa.

RESUMO Objetivou-se avaliar a qualidade física e fisiológica de sementes salvas de feijão-caupi (Vigna unguiculata L. Walp.) utilizadas no semiárido brasileiro e compará-las com as variedades de sementes certificadas. Foram testadas 37 amostras de sementes salvas oriundas de diferentes municípios do Rio Grande do Norte e duas variedades de sementes certificadas (BRS Guariba e BRS Pujante), provenientes do campo de produção da Embrapa Produtos e Mercado, Petrolina, PE. Para avaliação da qualidade física, as sementes foram submetidas aos testes de grau de umidade, peso hectolítrico, peso de mil sementes e pureza física. Na avaliação da qualidade fisiológica testou-se a germinação, primeira contagem de germinação, emergência em campo, índice de velocidade de emergência, matéria seca de parte aérea e envelhecimento acelerado. As sementes salvas de feijão-caupi apresentaram grandes diferenças, sugerindo tanto a influência da variabilidade genética como dos diferentes ambientes de cultivo. A utilização de sementes salvas de feijão-caupi pelos pequenos produtores das áreas semiáridas do nordeste do Brasil se constitui em prática inviável por se tratar de sementes de qualidades física e fisiológica inferiores às sementes de origem certificadas. | ABSTRACT This study evaluated the physical and physiological attributes of saved cowpea seeds (Vigna unguiculata L. Walp.) used in the Brazilian semi-arid area and compared them with certified seed varieties. The study tested 37 saved seed samples from the state of Rio Grande do Norte and two varieties of certified seeds (“BRS Guariba” and “BRS Pujante”) from the production field of Embrapa Products and Market, Petrolina, PE, Brazil. The seeds were tested for moisture, hectoliter weight, weight of 1,000 seeds, and physical purity to evaluate the physical quality. Germination, first germination count, field emergence, emergence rate index, shoot dry mass, and accelerated aging were tested for physiological quality. The saved cowpea seeds showed great differences, suggesting the influence of genetic variability and different growing environments. The use of saved cowpea seeds by small farmers in the semi-arid areas of Northeastern Brazil is impractical, because these seeds have inferior physical and physiological qualities compared to certified cowpea seeds.

RESUMO A adubação nitrogenada na videira apresenta-se como um fator limitante na produção, visto que seu excesso ou deficiência são capazes de propiciar alterações na quantidade e qualidade final dos frutos. Assim, o objetivo deste trabalho foi avaliar os parâmetros produtivos da videira 'Isabel Precoce' submetida a adubação nitrogenada e orgânica na região semiárida do Oeste Potiguar. O experimento foi implantado na Fazenda Experimental da UFERSA, em Mossoró, RN, cujo clima é semiárido. O solo da área é um Argissolo Vermelho Distrófico de textura arenosa. A pesquisa foi realizada em dois ciclos de produção. O delineamento experimental utilizado foi blocos casualizados com seis repetições, em esquema fatorial 5 x 2, que corresponderam a 5 doses de fertilizante nitrogenado (0, 30, 60, 90 e 120 kg ha-1), na ausência e presença de adubação orgânica (0 e 20 m3 ha-1 esterco bovino). Foram avaliados número de cachos por planta, produção por planta e produtividade, bem como peso, comprimento e largura dos cachos, número de bagas por cacho e peso de dez bagas. A aplicação das doses de nitrogênio (N), bem como o uso ou não de adubo orgânico (AO) no solo, conferiram efeito significativo (p=0,05) para todos os componentes avaliados. A dose de 60 kg ha-1 de N na presença do AO foi a que proporcionou os melhores resultados nas variáveis analisadas. A elevação dos níveis de N, a partir da dose de 60 até 120 kg ha-1 combinadas ou não a fonte orgânica, inibiram os componentes produtivos da videira ´Isabel Precoce´. | ABSTRACT Nitrogen fertilization is a limiting factor for grapevine production; its excess or deficiency can cause changes in fruit quantity and quality. Thus, the objective of this work was to evaluate productive parameters of grapevines of the Isabel-Precoce cultivar subjected to nitrogen and organic fertilization in the western semiarid region of the state of Rio Grande do Norte (RN), Brazil. The experiment was conducted at the Experimental Farm of the Federal Rural University of the Semi-Arid Region, in Mossoró, RN, Brazil, during two production cycles. The soil of the area used was classified as dystrophic Red Argissolo (Udult) of sandy texture. The experiment was conducted in a randomized block design with six replications, using a 5×2 factorial arrangement, with 5 nitrogen fertilizer rates (0, 30, 60, 90, and 120 kg ha-1) and two organic fertilizer rates (0, and 20 m3 ha-1 of bovine manure). The production components number of bunches per plant, grape production per plant, grape yield, weight, length and width of bunches, number of berries per bunch, and ten-berry weight were evaluated. The nitrogen rates and organic fertilizer rates used were significant (p=0.05) for all evaluated components. The N rate of 60 kg ha-1 combined with the organic fertilization generated the best results for the analyzed variables. N rates from 60 to 120 kg ha-1, applied singly or combined with organic fertilizer, hindered the production components of the Isabel-Precoce grapevines.

ABSTRACT Swine wastewater can be used as a biofertilizer and promote significant improvements in soil physical-chemical attributes and yield. The objective of this study was to evaluate the effects of swine wastewater application on soil and maize yield. The experiment was conducted at the Agricultural Sciences Center of the Federal University of Piauí, in Teresina, Piauí, Brazil, from August to November 2015. The experimental design used completely randomized blocks in split-plot scheme, with five doses of swine wastewater (0, 25, 50, 75 and 100 m3 ha-1) in the plots and two soil depths (0.20 and 0.40 m) in the subplots, with four replications. Exchangeable contents of calcium, magnesium, phosphorus, potassium and sodium, electrical conductivity, pH, sum of bases, base saturation, potential acidity and cation exchange capacity, and crop yield were evaluated. Results showed calcium, magnesium, sum of bases and cation exchange capacity increased with elevated levels of swine wastewater. Potassium and sodium contents however decreased with doses of 51.58 and 52.28 m3 ha-1, respectively. Except for potassium and potential acidity, variables showed higher values at the 0-0.20 m depth. | RESUMO A água residuária da suinocultura pode ser usada como biofertilizante e promover melhorias significativas nos atributos físico-químicos do solo e na produtividade. Objetivou-se avaliar os efeitos da aplicação da água residuária da suinocultura no solo e na produtividade do milho-verde. O experimento foi conduzido no Centro de Ciências Agrárias da Universidade Federal do Piauí, em Teresina, Piauí, no período de agosto a novembro de 2015. O delineamento experimental adotado foi em blocos casualizados em esquema de parcela subdividida, com 4 repetições, sendo os tratamentos constituídos por cinco doses de água residuária da suinocultura (0, 25, 50, 75,100 m3 ha-1) nas parcelas e duas profundidades do solo (0,20 e 0,40 m) nas subparcelas. Foram avaliados os teores trocáveis de cálcio, magnésio, fósforo, potássio e sódio, condutividade elétrica, pH, soma de bases, saturação por base, acidez potencial e capacidade de troca de cátions, e a produtividade da cultura. Os resultados demonstraram que os teores de cálcio, magnésio, soma de base e capacidade de troca de cátions aumentaram com a elevação dos níveis de água residuária da suinocultura, no entanto os teores de potássio e sódio reduziram a partir das doses de 51,58 e 52,28 m3 ha-1, respectivamente. Com exceção do potássio e acidez potencial, as demais variáveis apresentaram maiores valores na profundidade de 0-0.20 m.